1. Field of the Invention
The present invention relates to photographic processing equipment. In particular, the present invention is a photographic print cutting and sorting apparatus.
2. Description of the Prior Art
In commercial photographic processing operations, very high rates of processing need to be achieved and maintained in order to operate profitably. To expedite the photographic processing, orders containing film of similar type and size are spliced together for developing. As many as 500 to 1000 rolls of 12, 20, 24 and 36 exposure film may be spliced together for processing and printing purposes.
After developing, the photographic film contained in the film negatives are printed in an edge-to-edge relationship on a continuous strip of photosensitive paper by a photographic printer. The photographic printer causes high intensity light to be passed through a negative and imaged on the photographic print paper. The photographic emulsion layer on the print paper is exposed and is subsequently processed to produce a print of the image contained in the negative.
After the strip of photographic print paper has been processed to produce prints, a photographic paper cutter cuts individual prints from the strip. The prints are then sorted by customer order, either manually or automatically, and ultimately packaged and sent to the customer.
Automatic print paper cutters have been developed which automatically cut the print paper into individual prints. These automatic paper cutters are controlled by indicia which are placed along the print paper by the photographic printer. Typically the indicia are of two types: cut marks and end-of-order marks. Cut marks indicate the desired location of a cut between adjacent prints. End-of-order marks, which typically appear along the opposite edge of the print paper from the cut marks, indicate the end of a customer's order. The automatic paper cutter includes a sensor which senses the cut marks and causes the individual prints to be cut from the strip at desired locations. The separated prints are passed to an order packaging or grouping device which groups the prints in response to the end-of-order marks which are sensed by the automatic cutter.
The desire for higher rates of processing within commercial photographic processing operations has led to the development of extremely high speed automatic paper cutters. One example of such an automatic paper cutter is the Pako PC305 print cutter manufactured by Pako Corporation, the assignee of the present application. A description of the Pako PC305 may be found in U.S. Pat. No. 4,128,887 by G. Strunc and F. Laciak. The Pako PC305 print cutter is capable of cutting over 25,000 prints per hour (i.e. over seven prints per second).
Photographic print sorting devices have also been developed for sorting individually cut photographic prints into "good," "remake," and "reject" prints. One successful form of photographic print sorting apparatus is the Pako PS305 print sorter manufactured by Pako Corporation, the assignee of the present application. A general description of this type of photographic print sorting apparatus may be found in a U.S. patent application by R. E. Diesch and C. L. Eutenuer entitled "PHOTOGRAPHIC PRINT STACKING DEVICE," Ser. No. 21,091 filed Mar. 16, 1979 and assigned to the same assignee as the present application. The PS305 print sorter is used in conjunction with the Pako PC305 paper cutter described above. The PC305/PS305 cutting and sorting apparatus is controlled by a common microprocessor housed within the PC305 paper cutter. A remake/reject indicia sensor mounted near the knife assembly of the PC305 cutter senses indicia on the prints which indicate the presence of a remake or reject print. The PS305 sorter has a main conveyor line for good prints, a first branch conveyor line for remake prints, and a second branch conveyor line for reject prints. A first diverter may be actuated to divert remake and reject prints from the main conveyor line into the first branch conveyor line. A second diverter may be actuated to divert reject prints from the first branch conveyor line into the second conveyor branch line. Operation of the first and second diverters is controlled by the microprocessor as a function of the signals from the remake/reject indicia sensor. Print stacking devices are positioned at the discharge end of the main conveyor line and the first branch conveyor line for stacking the good and remake prints, respectively. The reject prints are driven out the bottom of the apparatus into a waste container or the like.
Another successful automatic print sorting apparatus is the Pako Photopacker manufactured by Pako Corporation. The Pako Photopacker cuts, sorts, conveys, and packs photographic prints into a packaging envelope. In addition, the Pako Photopacker also cuts and packs photographic film negatives into the same packaging envelope. The print sorting portion of the Pako Photopacker is described in U.S. Pat. No. 4,114,349 by G. A. Jensen, L. A. Larson, and R. E. Diesch which is assigned to Pako Corporation. The Pako Photopacker includes a main conveyor line for good prints, and first and second branch conveyor lines for reject and remake prints. Diverters are positioned at the openings of the first and second branch conveyor lines for diverting reject and remake prints into the first and second branch conveyor lines, respectively. Positioned near the end of each of the conveyor lines of the Pako Photopacker is a print sensor formed by a light source and a light sensor. The control circuitry of the Pako Photopacker monitors the signals from the three print sensors to determine when the trailing edge of a print has passed the print sensor. The paper cutter used in conjunction with the Photopacker advances a length of photographic print paper past the knife of the paper cutter and stops the paper at a position in which the desired cut location is aligned with the knife assembly. The paper cutter then provides a signal to the Photopacker control circuitry indicating that the paper has been advanced and is at the cut position. When the Photopacker control circuitry receives a signal from one of the three print sensors indicating that the trailing edge of the previous print has just passed the print sensor, the Photopacker control circuitry then provides an enable signal to the paper cutter which permits the next print to be cut. The process is then repeated with the Photopacker control circuitry waiting for the print to reach its destination, while the paper cutter advances the paper, stops the paper at the cut position, provides a signal to the Photopacker indicating that the paper is stopped, and waits for the next cut enable signal from the Photopacker control circuitry. The purpose of this arrangement is to prevent jamming within the conveyor lines. If a print has not reached its destination, but rather is hung up within the conveyor lines, subsequent prints would cause further jamming to occur.
Although the print sensing arrangement of the Pako Photopacker avoids large jams of prints from occurring, and provides early warning to the operator of the existence of a possible jam, it does have disadvantages. The most important disadvantage is that it reduces the operating speed of the cutting and sorting apparatus. With the development of very high speed photographic paper cutters, the print sensor arrangement used in the Pako Photopacker prevents the paper cutter from operating at its full capacity. Rather, the paper cutter is forced to stop and wait until the print has reached its destination at the end of the conveyor lines.
There is a continuing need for improved photographic print cutting and sorting apparatus which provides protection against print jams, while permitting high speed operation of the photographic paper cutter.